<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>

    <!-- 表单验证 -->
    <p>用户名：只能由数字和字母组成且数字不能开头，长度4-10位</p>
    <input type="text" placeholder="请输入用户名">
    <br>
    <p>密码：只能由数字和字母组成且数字不能开头，长度4-10位</p>
    <input type="password" placeholder="请输入用户名">
    <br>
    <p>确认密码</p>
    <input type="text" placeholder="请输入用户名">
    <br>
    <p>验证码</p>
    <input type="text" placeholder="验证码">
    <span>1234</span>
    <button>刷新</button>

    <p>
        <button>注册</button>
    </p>
    
</body>
</html>